Induction-type alternating-current relays



Jan. 7, 1958 w. K. SONNEMANN 2,819,430

I INDUCTION-TYPE ALTERNATING-CURRENT RELAYS Filed Feb. 26, 1954 0' 0 9 Contact Travel I l (E Fig.5. 5E SE I I I l I I I I I I I I l l l I I l n l l 4 -e -e 0 9 I40 0 Contact Travel WITNESSES: INVENTOR 4775/ William K.Sonnemonn.

I 52 66 Wa W ATTORNEY United States Patent O INDUCTION-TYPE ALTERNATING-CURRENT RELAYS William K. Sonnemann, Roselle Park, N. J., assignor to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application February 26, 1954, Serial No. 412,788

13 Claims. (Cl. 317-156) This invention relates to devices responsive to alternating quantities, and it has particular relation to inductiontype alternating-current regulating relays which operate with substantial time delay.

In the application of electroresponsive relays to electrical systems for regulating purposes it has been the prac tice to provide relays having substantial time delay for the purpose of preventing operation of the relay for momentary deviations of the regulated quantity from a predetermined normal value. Such time delay is ordinarily obtained by providing the relay with adjustable damping means.

In addition, time delay regulating relays are provided which effect the regulation of different values of operating quantities such. as current and voltage. Such relays are also adapted to provide regulation of an operating quantity between various values thereof.

In accordance with the invention a time delay device, such as a regulating relay, isprovided with improved time delay characteristics. In addition, adjustments are provided by means of which calibration of the relay is obtained for a substantial range of values of an operating quantity. One of the adjustments preferably is in the form of a closed adjustable winding which surrounds magnetic flux produced in the relay. A further adjustment is provided to adjust the limiting values of an operating quantity between which regulation is desired. This adjustment may take the form of adjustable circuit con trolling contact means which are spaced along the path of movement of the translating means of the relay.

In a preferred embodiment of the relay an E shaped electromagnet is provided which has three pole pieces located in a common plane and connected magnetically by a magnetic bridge portion. Electromagnets having pole pieces so arranged are disclosed in my copending patent applications, Serial Nos. 251,234, now Patent No. 2,697,- 187, and 274,845, now Patent No. 2,752,539, filed respectively October 13, 1951, and March 5, 1952. Anenergizing winding surrounds the center pole piece while a closed circuit lagging winding. surrounds one of the outer pole pieces. Translating means in the form of an electroconductive armature is located adjacent the pole faces of the pole pieces. The pole faces provide three time displaced magnetic flux components for the purpose of establishing a shifting magnetic field for the armature. Independent adjustments may be provided, if desired, for the magnetic paths followed by two of the magnetic flux components. Preferably, adjustable damping is provided for the armature of the relay.

The armature is preferably in the form of a rotatably mounted disc of spiral configuration and is biased in a predetermined direction in any suitable manner, such as by a conventional spiral spring which is adjustable for the purpose of adjusting such bias. The disc is secured to av rotatable shaft which carries'a contact member movable between a pair of fixed. adjustable contact members spaced-along the path of movement: of the movable contact for engagement therewith upon predetermined energization of the relay. The pair of fixed contacts are preferably adjustable for varying the upper and lower limiting values of an operating quantity, between which regulation of such quantity is desired.

The energizing winding may be provided with suitable taps to permit adjustment of the shifting magnetic field for effecting the calibration of the relay for operating quantities having values represented by such taps. An additional fine adjustment may be provided to take care of any deviations of the operating quantity from the rated values represented by the taps. For this purpose the closed circuit lagging Winding is rendered adjustable to vary the strength of the shifting magnetic field over a substantial range.

It is, therefore, an object of the invention to provide an improved electroresponsive relay device.

It is another object of the invention to provide a time delay regulating relay device having improved operating time characteristics.

It is still another object of the invention to provide a time delay regulating relay device having an adjustable time delay and having separate adjustments for controlling energization of the relay and for controlling the limiting values of an energizing quantity between which regulation is desired.

It is a still further object of the invention to provide a, time delay regulating relay device having translating means movable between two operating position under control of two opposing forces which increase at different rates as the translating means moves toward one of the operating positions in response to predetermined energization of the relay device.

It is another object of the invention to provide atime delay regulating relay device as defined in the preceding paragraph wherein adjustable damping is provided for the translating means.

It is still another object of the invention to provide a time delay regulating relay device as defined in the two preceding paragraphs wherein one of said forces is produced by biasing means proportioned to balance said other of said forces ata predetermined point within the range of movement of the translating means to thereby provide a stationary position of the translating means intermediate said operating positions for a predetermined magnitude of said other said forces.

Other objects of the invention will be apparent from the following. description taken in' conjunction with the accompanying drawings, in which:

Fig. l is a view in side elevation, with parts broken away and parts schematically shown, of an electrical relay embodying the invention;

Fig. 2 is a view in rear elevation, with parts schematically shown, of an electro'magnet suitable for the relay of Fig. 1;

3 is a view in top plan of the relay illustrated in Fig. 4 is a' graphical representation showing certain relationships between relay torque and relay contact travel for a prior art relay;

Fig. 5 is a graphical representation showing certain relationships between r'elay torque and relay contact travelfor the relay illustrated in Figs. 1, 2, and 3; and

Fig. 6 is a view taken along the line VI-Vl of Fig. 1.

Referring to the drawing, Fig. 1 illustrates a relay R which is designed for energization in accordance with a variable alternating quantity. This relay includes a sta tor 1 in which a shaft 3 carrying an electrocon'ductive armature 5 is mounted for rotation. Conveniently, the electroconductive armature 5- maybe in the form of a disc constructed of aluminum or copper. An electromagnet '7 is provided for the purpose of producing a shifting magnetic field within which a"- portion" of the armature 5 is located. As is well understood in the art, a shifting magnetic field operates on the electroconductive armature to produce a torque which urges the disc in a predetermined direction about its axis.

Preferably, adjustable damping is provided for the armature 5. Conveniently, such damping may be provided by means of a horseshoe-shaped permanent magnet 9, as shown in Fig. 6, constructed of a high-coercive permanent-magnet material. The magnet 9 has its two pole faces, which are identified by the reference characters N for north pole and S for south pole, positioned adjacent one face of the armature 5. A plug 11 of soft magnetic material is positioned on the opposite side of armature 5 to define with the pole faces two air gaps within which the armature rotates. The magnet 9 and the plug 11 may be secured to a suitable holder 13. constructed of nonmagnetic material such as die-cast aluminum alloy. Preferably, the plug 11 is adjustable relative to the magnet 9 to change the lengths of the air gaps and consequently the strength of the magnetic field therein. The plug may have screw threads in threaded engagement with threads provided in the 'holder 13. By rotation of the plug 11 the plug may be moved towards or away from the associated magnet 9 to modify the strength of the magnetic field within which the armature 5 rotates. As is well understood in the art, such rotation of the armature provides a damping force acting between the stator to which the holder 13 is secured and the electroconductive armature.

A bias is provided for the shaft 3. To this end a spiral control spring 15 is provided having its inner end secured to the shaft 3 and its outer end secured to a portion of the stator 1. This spring normally is disposed in a plane substantially transverse to the shaft 3, but is illustrated as being rotated from its normal position in Fig. 1 to illustrate the convolutions thereof. The spring is shown as occupying its normal position in Fig. 3. As the disc 5 rotates in the direction represented by the arrow 5A of Fig. 3, the spring 15 winds up and exerts a torque on the disc in the direction represented by the arrow 5B which increases as the disc rotates.

In order to produce a response for predetermined energizations of the relay, a movable contact 17 is secured to the shaft 3 for movement between a pair of fixed contacts 19 and 21 which may be secured to the stator 1 in any desired manner. Engagement of the contact 17 and the contact 19 is effective to establish a first electrical circuit whereas engagement of the contacts 17 and 21 operates to establish a second electrical circuit. Such circuit completions may be employed for any desired purpose. For example, the contact 19 may be located to represent a first value of a relay operating quantity whereas the contact 21 may be positioned to represent a second value of the operating quantity. As will appear hereinafter, the relay may be calibrated to have the movable contact 17 assume a stationary position at a number of different points intermediate the contacts 19 and 21 when the relay is energized by an operating quantity of predetermined value. Consequently, the contacts 19 and 21 may be included in separate circuits which contam apparatus effective upon completion of such circuits resulting from deviation of the operating quantity from a predetermined value to effect the restoration of the operating quantity to such predetermined value.

The time required for movement of the movable contact 17 from a stationary position intermediate the con tacts 19 and 21 into engagement with either of the contacts 19 and 21 depends on the torque developed by the electromagnet 7 which acts on the armature 5, the bias exerted by the spring 15 on the armature, the location of the contacts 17, 19 and 21 and the magnitude of the dampmg which is applied to the armature by the damping magnet assembly. The damping action produced by the permanent magnet assembly may be adjustable to vary the time of response of the relay device.

In accordance with the present invention, the disc 5 may be provided with a spiral configuration as illustrated in Fig. 3. By inspection of Fig. 3, it is observed that as the disc 5 rotates in the direction represented by the arrow 5A, the radius of the disc in the region of the electromagnet 7 increases. Consequently, constant energization of the electromagnet 7 sufiicient to urge the disc 5 in the direction 5A produces a torque on the disc which Increases as the disc rotates in such direction.

It is observed that the disc 5 is subjected to a number of forces during operation of the relay. One of these forces is exerted by the spring 15 and another of these forces is produced by energization of the electromagnet 7. These twoforces act on the disc 5 in opposing relation. Consequently, when these two forces are of substantially equal magnitudes, zero resultant force is applied to the disc 5 and the disc assumes a stationary position.

Referring to Fig. 2, it will be noted that the electromagnet 7 includes an E-shaped magnetic structure 23 having three pole pieces 23A, 23B and 23C disposed substantially in a common plane. The magnetic structure 23 may be constructed of a'plurality of laminations of soft magnetic material, such as soft iron, each having a shape illustrated in Fig. 2. Alternatively, each of the laminations may be constructed of two or more parts and the parts may be associated by means of butt or interleaved joints which are well known in the art.

The pole pieces 23A, 23B and 230 have pole faces 23a, 23b and 230, respectively, which are disposed in a common plane which is transverse to the plane of the pole pieces 23A, 23B and 23C.

In order to eifect energization of the electromagnet 7, a winding 25 is provided which may surround one of the pole pieces 23A, 23B or 23C. Conveniently, the winding 25 surrounds the pole pieces 23B and may have an adjustable number of turns as represented by taps 25A, 25B. Each of the taps may represent a separate value of an operating quantity and the taps are provided to permit calibration of the relay for such values of an operating quantity.

The winding 25 may be connected for energization in accordance with any desired alternating quantity. For example, the winding 25 may be energized in accordance with alternating current. However, it will be assumed that the winding 25 is energized through a voltage transformer 27 in accordance with alternating voltage of a circuit represented by the conductors L1 and L2. It will be assumed that the conductors L1 and L2 represent the two conductors of a two wire, single-phase alternatingcurrent circuit operating at a frequency of 60 cycles per second, although the conductors L1 and L2 may also represent two phase conductors of a polyphase circuit.

When the winding 25 is energized, a magnetomotive force is produced, creating a shifting magnetic field in the area occupied by a port-ion of the armature 5. In order to decrease the magnetic reluctance offered to the flow of magnetic flux, a magnetic member 29 is spaced from the pole faces 23a, 23b and 230 to provide air gaps between the member 29 and the pole faces. The armature 5 passes through these air gaps. The magnetic member 29, like the magnetic structure 23, may be constructed of soft magnetic laminations, such as soft iron, each having a shape similar to that illustrated in Fig. 2.

When energized, the winding 25 produces a magneto motive force which directs magnetic flux components through parallel paths. One of the paths includes the pole piece 23B, the pole piece 23A, a portion of the magnetic member 29, the air gaps between the member 29 and the pole faces 23a and 23b and a portion of the bridge portion 30. The second path includes the pole piece 238, the pole piece 23C, a portion of the member 29, the air gaps between the member 29 and the pole faces 23b and 230 and a portion of the bridge portion 30. Magnetic fluxes which flow between the magnetic member 29 and the pole pieces 23A, 23B and 230 are represented in Fig. 2 y ew a Pb and In order to establish a phase displacement between the magnetic fluxes 5,, 5 and et a closed lagging winding 31 may surround either of the pole pieces 23A or 230. As illustrated, the winding 31 surrounds the pole piece 23A. It may be shown that the magnetic flux components traversing the air gaps reach their maximum values in the same directions through the air gaps in the order 4),, and 4: This produces a shifting magnetic field and applies a torque between the electromagnet 7 and the electroconductive armature which opposes the torque produced by the spring 15 and tends to urge the armature from left to right as viewed in Fig. 2.

The magnetic parts connecting the pole pieces 23A, 23B and 23C may have uniform cross-sections throughout their lengths. However, if it is desired to provide further adjustments for the relay torque characteristics, at least one of the magnetic paths offered to magnetic flux produced by current flowing in the winding 25 may be adjustable. In Fig. 2, both of the paths are independently adjustable. The adjustments may be effected by provision of one or more openings in the magnetic parts for reception of adjustable mangetic elements A or B. The magnetic elements may take the form of plugs which are screw operated. For example, in Fig. 1 the plug A has a large magnetic head 35 with a stud 37 projecting from one end thereof. The stud 37 is in threaded engagement with a portion of the stator 1. The head 35 is constructed of soft magnetic material such as soft iron or steel. It is located within an opening provided in the magnetic structure 23 and is slidable through the opening in response to rotation of the plug. If desired, the head 35 may be spaced from the walls of the opening by a thin-walled non-magnetic sleeve. For example, a thin plating of non-magnetic material, such as copper, may be applied to the head 35 for this purpose.

It will be noted that each of the plugs, for example the plug B, varies the series magnetic reluctance of the magnetic path with which it is associated.

Suitable positions for the plugs A and B are shown in Fig. 2. It will be understood that the openings provided in the magnetic structure 23 to receive the plugs leave bridges A1, A2, B1 and B2 which saturate for low values of magnetic flux therethrough. When the plugs A and B are introduced into their associated openings, they shunt magnetic flux around their associated bridges and thus alter the magnetic reluctances of the paths which contain the plugs.

It will be recalled that taps such as the taps 25A and 25B are provided on the energizing winding 25 for the purpose of permitting calibration of the relay. In conventional practice, each of the taps would be rated at a specific value of an operating quantity. However, in practice, values other than these specific values may be encountered.

In order to provide an additional adjustment permitting calibration of the relay the closed winding 31 has its terminals connected across an adjustable impedance which is preferably an adjustable resistor 33. The winding 31 serves essentially as the secondary winding of a transformer wherein the winding 25 represents the primary winding. Because of the magnetic coupling between the two windings, energization of the winding 25 causes a voltage to be induced in the winding 31 which causes current to flow in the winding 31 which produces a magnetomotive force acting in opposition to the magnetomotive force produced by energization of the winding 25. The value of the magnetomotive force produced by winding 31 may be controlled by adjustment of the resistor 33 to thereby control the phase displacement of the magnetic fluxes t, o and and consequently, the torque developed by the electromagnet 7. Since the magnetic flux flowing in the pole pieces 23B is determined by the resultant of the magnetomotive forces produced by the windings 25 and 31, the adjustable resistor 33 also provides a convenient adjustment for the magnitude of magnetic flux 6 flowing in the pole piece 23B for each energization of the winding 25. Consequently, by adjustment of the resistor 33, the movable contact 17 may be moved to a number of different stationary positions for energization of the relay by a predetermined value of an energizing quantity.

Although the invention has been described adequately above it will be helpful to consider the present understanding of the theory of operation of the invention. In Figs. 4 and 5 a number of curves have been plotted on coordinates wherein ordinates represent torque acting between the rotor and stator of the relay and wherein abscissae represent degrees of travel of the movable contact 17.

With reference to Fig. 4, there is illustrated a graphical representation showing certain relationships between relay torque and relay contact travel for a relay employing an armature of conventional circular configuration. Consequently, it will be assumed for present purposes that the armature 5 is of circular configuration as viewed in Fig. 3. It will also be assumed that the abscissa 0 represents the position of the movable contact 17 when it is in engagement with the fixed contact 21 and that the abscissa 140 represents the position of the movable contact 17 when it is in engagement with the fixed contact 19. It will be further assumed that 140 represents the maximum range of travel of the contact 17 and corresponds to a voltage range of 30 volts with upper and lower limiting values of voltage being 135 and volts, respectively.

Let it now be assumed that energization of the relay by a voltage of 105 volts is effective to produce a torque T which may be represented by a curve 1E and which is sufficient to effect engagement of the contacts 17 and 21. in a similar manner it will be assumed that energization of the relay by a voltage of volts is efiective to produce a torque T acting between the disc and the electromagnet which may be represented by a curve 2E and which is sufficient to e'fiect engagement of the contacts 17 and 19. By reason of the preliminary assumption of a circular configuration of the disc 5 the curves 1E and 2E may be illustrated as horizontal lines extending across the path of travel of the contact 17.

As described hereinbefore, when the relay is sufiiciently energized the armature 5 moves in the direction represented by the arrow 5A to wind up the spring '15 which biases the disc in the direction represented by the arrow 58 with a torque which increases as rotation of the armature 5 continues in the direction represented by the arrow 5A. This spring torque acts on the armature 5 in the opposite direction from the electrical torque acting between the disc and electromagnet which is produced by energization of the relay. Consequently, when the spring torque and the electrical torque are substantially of equal value, zero resultant torque is applied to the armature with the result that the armature remains stationary. For present purposes it will be assumed that the spring torque and electrical torque are of substantially equal magnitude when the relay is energized by a voltage of 105 volts and the movable contact occupies the 0 position and when the relay is energized by a voltage of 135 volts with the movable contact in the position. Consequently, inasmuch as the contacts 19 and 21 are located at points representative of values of 105 and 135 volts, respectively, movement of the contact 17 ceases just as the contact 17 engages the contacts 19 and 21 when the relay is energized respectively by 105 and 135 volts. I in order to provide such characteristics of the relay it is necessary to provide a spring 15 having properties represented by curve S. As illustrated in Fig. 4, the curve S intersects the curves 1e and 2e at points which corre spond to 0 and 140 positions of the contact 17, respectively. The curve S intersects the zero torque line at -6 which indicates the amount of initial spring windup involved.

If it be assumed that the normal voltage impressed across the conductors L1 and L2 is 120 volts and that the 7 winding 25 is connected for energization in accordance with such voltage, then the electrical torque represented by the curve 4E willbe produced between the armature and the electromagnet 7. By inspection of Fig. 4 it is noted that the curves S and 4E intersect at a point corresponding to the contact position 9 which, for the particular circular disc relay presently under discussion, has been found to be 65.7. This is the stationary position assumed by the movable contact 17 when the relay is energized in accordance with a voltage of a value of 120 volts.

Now let it be assumed that the relay is energized in accordance with a voltage having a value of 123.6 volts to produce an electrical torque acting between the disc and the electromagnet which is represented by the curve 3E. It is noted that the curve S and the curve 3E intersect at a point corresponding to the contact position 6 which,for the particular relay under discussion, is found "to be 82.9". This means that when the voltage of the circuit represented by the conductors L1 and L2 is increased three percent from a value of 120 volts to a value of 123.6 volts the disc 5 rotates from its stationary position of 65.7 against the bias of the spring 1.55 toward the contact 19 until a new point of equilibrium is reached at 829. Consequently, for an increase of voltage of the associated circuit of 3.6 volts from a value of 120 volts, the disc moves in the direction represented by the arrow 5A through an angle of 172.

Now let it be assumed that the disc of circular configuration is replaced by one having a spiral configuration, as shown in Fig. 3. With reference to Fig. 5, there is illustrated a graphical representation showing certain relationships between relay torque and relay contact travel for a relay employing a disc of spiral configuration. As there shown, the. same 140 range of contact travel is employed as was done in the previous example. It will be further assumed that the relay is calibrated by means of the taps 25A and 25B and the resistor 33 to cause the disc 5 and, therefore, the contact 17 to be stationary at the 70 point of travel of the contact 17 when the relay is energized in accordance with a voltage of a value of 120 volts. With such energization of the relay an electrical torque is produced between the disc 5 and the electromagnet 7 which is represented by the curve 7E in Fig. 5.

By inspection of Fig. 5 it is noted that the curve 7E is not horizontal as was the case with the several electrical torque curves 1E, 2E, 3E and 4E illustrated in Fig. 4. Instead the curve 7E has a slope and this may be explained by considering the configuration of the armature 5. By reason of the spiral configuration of the armature 5, the armature presents an increasing effective portion to the shifting magnetic field produced by the electromagnet 7 as the disc is rotated in the direction represented by the arrow 5A in response to constant energization of the relay suflicient to initiate such rotation. Consequently, the electrical torque produced between the disc and the electromagnet by such constant energization increases until it attains a magnitude substantially equal to the magnitude of the opposing spring torque at which point rotation of the disc ceases.

Let it now be assumed that the relay is energized in accordance With'a voltage having a value of 123.6 volts to produce an electrical torque acting between the disc and electromagnet which is represented by the curve 5B. This value of voltage is the same as that which was required to produce a torque having the curve 3E in the previous example. It will be further assumed that the point of balance between the spring torque and the electrical torque represented by the curve 5E occurs precisely at the 140 point of travel of the movable contact 17. Inasmuch as the point of equilibrium between the spring torque and the electrical torque represented by the curve 7B'is" established at the 70 point of travel of the movable contact 17, a spring torque curve 28 maybe constructed as shown in Fig. 5 to intersect the electrical torque curves 5E and 7E at the 140 and 70 points of travel of the movable contact 17, respectively. The curve 28 then rep resents characteristics of the spring which must be met to provide the desired 140 and 70 stationary positions of the movable contact 17. The curve 25 intersects the zero torque line at -6 which indicates the amount of initial spring windup involved. In order to cause the movable contact 17 to be stationary at the 0 point of travel of the contact 17, it is necessary to effect energization of the relay in accordance with a voltage of a value necessary to produce a torque represented by the curve 6E as shown in Fig. 5. By calculation, the value of this voltage is found to be 115.2 volts.

By inspection of Fig. 5 it is observed that the electrical torque curves 5E, 6E and 7E radiate from the -6 point of travel of the contact 17. This is a theoretical point and may be varied by varying the degree of the spiral cut on the periphery of the disc 5 as Well as by varying the location of the disc 5 relative to the electromagnet 7.

By comparison of the two types of relays under consideration, it will be observed that an increase in energization of the spiral disc relay of 3.6 volts from a voltage of volts causes the movable contact thereof to move through an angle of 70 whereas thesame increase in the energization of the circular disc relay operates to rotate the contact 17 through only 17.2. Consequently, since the spiral disc rotates through an angle 4.07 times greater than the angle of rotation of a circular disc for the same increase in energization, it follows that the damping magnet 9 is 4.07 times as effective upon a disc of spiral configuration than it is upon a disc of circular configuration for the specific examples described. From this it follows that the time. required for the particular spiral disc relay under consideration to operate upon a voltage rise of 3.6 volts from a voltage of 120 volts is 4.07 times as great as the time required for a conventional circular disc relay to operate in response to the same increase in voltage from the normal voltage of 120 volts.

It will be recalled that in the discussion of the spiral disc relay the contacts 19 and 21 correspond to values of operating voltage of 123.6 volts and 115.2 volts, respectively, and that the contact 17 is static-nary at the 70 point of contact travel which is intermediate the contacts 19 and 21 for a normal voltage of a value of 120 volts. This setting of the relay produces a bandwidth of +3.6 volts and 4.8 volts. The bandwidth may be equalized to yield equal plus and minus increments of voltage either by adjusting the contact 21 to a predetermined position which is closer to the stationary contact 17 than the position in which the contact 21 is shown in Fig. 3, or by changing the normal stationary position of the contact 17 by means of the adjustable winding 31 to a position corresponding to an angle which is somewhat less than 70.

For certain installations it may be desirable to provide diiferent relay bandwidths while maintaining the same degree of maximum contact travel. To this end the spring 15 may be replaced by another spring having different characteristics. For example, in order to reduce the bandwidth of the described spiral dis relay below 8.4 volts, it is only necessary to substitute a weaker spring for the spring 15 and to utilize greater initial spring windup. Such a spring would have a torque curve exhibiting a lesser slope than the curve 28 of Fig. 5 but still intersecting the electrical torque curve 7E at a point corresponding to the 70 position.

Although the invention has been described with reference to certain specific embodiments thereof, numerous modifications thereof are possible. embodiments herein set forth are to be construed in an illustrative rather than in a limiting sense.

I claim as my invention:

1. In a time delay regulating relay device, a magnetic Consequently, the

stator structure having an air gap, an electroconductive rotor structure, means mounting the rotor structure for rotation through the air gap about an axis relative to the stator structure between first and second positions, said stator structure including winding means effective when energized for developing a first torque acting between the rotor and stator structures to urge the rotor structure toward said second position, said rotor structure having a configuration presenting a varying effective portion to the air gap such that said first torque increases in magnitude as the rotor structure rotates toward said second position in response to constant energization of said winding means, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of said rotor structure relative to the stator structure which has a first slope, biasing means connected between the stator and rotor structures for biasing the rotor structure toward said first position with a second torque which increases as the rotor structure rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torqueto the position of the rotor structure relative to the stator structure which has a second slope substantially different from said first slope to provide a point of intersection of said first and second curves within the range of rotation of said rotor structure, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said rotor structure intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the rotor structure at each of said first and second positions.

2. In a time delay regulating relay device, a magnetic stator structure having an air gap, an electroconductive rotor structure, means mounting the rotor structure for rotation through the air gap about an axis relative to the stator structure between first and second positions, said stator structure including winding means effective when energized for developing a first torque acting between the rotor and stator structures to urge the rotor structure to ward said second position, said rotor structure having a configuration presenting a varying effective portion to the air gap such that said first torque increases in magnitude as the rotor structure rotates toward said second position in response to constant energization of said winding means, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of said rotor structure relative to the stator structure which has a first slope, biasing means connected between the stator and rotor structures for biasing the rotor structure toward said first position with a second torque which increases as the rotor structure rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the rotor structure relative to the stator structure which has a second slope substantially different from said first slope to provide a point of intersection of said first and second curves within the range of rotation of said rotor structure, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said rotor structure intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the rotor structure at each of said first and second positions, said stator structure including adjustable means for adjusting the magnitude of said first torque to thereby adjust the stationary position of said rotor structure relative to said first and second positions for a constant energization of said winding means.

3. In a time delay regulating relay device, a magnetic stator structure having an air gap, an electroconductive rotor structure, rneans mounting the rotor structure for rotation through the air gap about an axis relative to the stator structure between first and second positions, said stator structure including winding means effective when energized for developing a first torque acting between the rotor and stator structures to urge the rotor structure toward said second position, said rotor structure having a configuration presenting a varying effective portion to the air gap such that said first torque increases in magni tude as the rotor structure rotates toward said second position in response to constant energization of said winding means, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of said rotor structure relative to the statorstructure which has a first slope, biasing means connected between the stator and rotor structures for biasing the rotor structure toward said first position with a second torque which increases as the rotor structure rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the rotor structure relative to the stator structure which has a second slope substantially different from said first slope to provide a point of intersection of said first and second curves within the range of rotation of said rotor structure, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said rotor structure intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the rotor structure at each of said first and second positions, said circuit controlling means being adjustable relative to said rotor structure about said axis for varying the range of rotation of the rotor structure.

4. In a time delay regulating relay device, a magnetic stator structure having an air gap, an electroconductive rotor structure, means mounting the rotor structure for rotation through the air gap about an axis relative to the stator structure between first and second positions, said stator structure including winding means effective when energized for developing a first torque acting between the rotor and stator structures to urge the rotor structure toward said second position, said rotor structure having a configuration presenting a varying effective portion to the air gap such that said first torque increases in magnitude as the rotor structure rotates toward said second position in response to constant energization of said winding means, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of said rotor structure relative to the stator structure which has a first slope, biasing means c0n nected between the stator and rotor structures for biasing the rotor structure toward said first position with a second torque which increases as the rotor structure rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the rotor structure relative to the stator structure which has a second slope substantially different from said first slope to provide a point of intersection of said first and second curves within the range of rotation of said rotor structure, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said rotor structure intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, damping means opposing rotation of said rotor structure relative to said stator structure with a third torque which varies substantially as a function of the rate of rotation of said rotor structure, and independent circuit controlling means spaced about said axis responsive to the arrival of the rotor structure at each of said first and second positions.

5. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure having first, second and third pole pieces, a first winding surrounding said first pole piece, said first winding being efiective when energized by an alternating quantity for directing magnetic flux in parallel through said second and third pole pieces, an electroconductive member mounted for rotation relative to the magnetic structure about an axis between first and second positions, said pole pieces having pole faces adjacent the electroconductive member for directing magnetic flux thereto, closed circuit means associated with said second pole piece for altering the time phase of magnetic flux passing there- 'through when the first winding is energized to establish a shifting magnetic field influencing the electroconductive member, said magnetic field developing a first torque acting between the magnetic structure and the electroconductive member, said electroconductive member having a configuration presenting a varying effective portion to said magnetic field such that said first torque increases in magnitude as the electroconductive member moves toward said second position in response to constant energization of said first winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the electroconductive member relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and the electroconductive member for biasing the electroconductive member toward said first position with a second torque which increases as the electroconductive member rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the electroconductive member relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of the electroconductive member, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of the electroconductive member intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alter hating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the electroconductive member at each of said first and second positions.

6. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure having first, second and third pole pieces, a first winding surrounding said first pole piece, said first winding being effective when energized by an alternating quantity for directing magnetic fiux in parallel through said second and third pole pieces, an electroconductive member mounted for rotation relative to the magnetic structure about an axis between first and second p sition, said pole pieces having pole faces adjacent the electroconductive member for directing magnetic fiux thereto, closed circuit means associated with said second pole piece for altering the time phase of magnetic flux passing therethrough when the first Winding is energized to establish a shift ing magnetic field influencing the electroconductive memher, said magnetic field developing a first torque acting between the magnetic structure and the elcctroconductive member, said electroconductive member having a configuration presenting a varying effective portion to said 12 magnetic field such that said first torque increases in magnitude as the electroconductive member moves toward said second position in response to constant energization of said first winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the electroconductive member relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and the electroconductive member for biasing the electroconductive member toward said first position with a second torque which increases as the electroconductive member rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of. the magnitude of said second torque to the position of the electroconductive member relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of the electroconductivc member, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of the electroconductive member intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the electroconductive member at each or" said first and second positions, said closed circuit means comprising a second winding and an adjustable impedance in series relation with the second winding, said impedance being adjustable for varying the impedance offered to current traversing the second winding produced by voltage induced therein by action of magnetic flux passing through the second pole piece, adjustment of said impedance being effective to vary the magnitude of said first torque to thereby vary the stationary position of the electrocond-uctive member relative to said first and second positions for a constant energization of said first Winding.

7. in a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure having first, second and third pole pieces, a first winding surrounding said first pole piece, said first winding being effective when energized by an alternating quantity for directing magnetic flux in parallel through said second and third pole pieces, an electroconductive member mounted for rotation relative to the magnetic structure about an axis between first and second positions, said pole pieces having pole faces adjacent the clectroconductive member for directing magnetic flux thereto, closed circuit means associated with said second pole piece for alternating the time phase of magnetic flux passing therethrough when the first winding is energized to establish a shifting magnetic field influencing the electroconductive member, said magnetic field developing a first torque acting between the magnetic structure and the electroconductive member, said electroconductive member having a configuration presenting a varying effective portion to said magnetic field such that said first torque increases in magnitude as the electroconductive member moves toward said second position in response to constant energization of said first winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the electroconductive member relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and the electroconductive member for biasing the electroconductive member toward said first position with a second torque which increases as the electroconductive member rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the electroconductive member relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of the electroconductive member, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of the electroconductive member intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of the electroconductive member at each of said first and second positions, said circuit controlling means being adjustable about said axis relative to the electroconductive member for varying the range of rotation of the electroconductive member to thereby vary the minimum and maximum values of a variable alternating quantity represented by said first and second positions.

8. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure having first, second and third pole pieces, a first winding surrounding said first pole piece, said first winding being effective when energized by an alternating quantity for directing magnetic flux in parallel through said second and third pole pieces, an electroconductive member mounted for rotation relative to the magnetic structure about an axis between first and second positions, said pole pieces having pole faces adjacent the electroconductive member for directing magnetic flux thereto, closed circuit means associated with said second pole piece for altering the time phase of magnetic flux passing therethrough when the first winding is energized to establish a shifting magnetic field influencing the electroconductive member, said magnetic field developing a first torque acting between the magnetic structure and the electroconductive member, said electroconductive member having a configuration presenting a varying effective portion to said magnetic field such that said first torque increases in magnitude as the electroconductive member moves toward said second position in response to constant energization or" said first winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the electroconductive member relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and the electroconductive member for biasing the electroconductive member toward said first position with a second torque which increases as the electroconductive member rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the electroconductive member relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of the electroconductive member, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of the electroconductive member intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, damping means opposing rotation of said electroconductive member relative to the magnetic structure with a third torque which varies substantially as a function of the rate of rotation of the electroconductive member, and independent circuit controlling means spaced about said axis responsive to the arrival of 'the electroconductive member at each of said first and second positions.

9. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure with first, second and third pole pieces having pole faces disposed substantially in a common plane, a magnetic member spaced from said pole faces to define an air gap between the magnetic member and each of the pole faces, an electroconductive armature mounted for rotation relative to the magnetic structure through the air gaps about an axis between first and second positions, said armature having a portion spaced from the axis positioned for movement through the air gaps, a winding surrounding said first pole piece effective when energized by an alternating quantity for directing magnetic flux in parallel through said second and third pole pieces, closed winding means surrounding said second pole piece for altering the time phase of magnetic fiux passing therethrough to establish a shifting magnetic field within the air gaps, said shifting magnetic field developing a first torque acting between said armature and said magnetic structure to urge the armature toward said second position, said armature having a spiral configuration presenting an increasing effective portion to said shifting magnetic field as the armature rotates toward said second position whereby the magnitude of said first torque increases as the armature rotates toward said second position in response to constant energization of said winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the armature relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and said armature for biasing the armature toward said first position with a second torque which increases as the armature rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of said armature relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of said armature, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said armature intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of said armature at each of said first and second positions, said circuit controlling means being adjustable relative to said armature about said axis to vary the range of rotation of said armature to thereby vary the minimum and maximum values of a variable alternating quantity represented by said first and second positions.

10. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure with first, second and third pole pieces having pole faces disposed substantially in a common plane, a magnetic member spaced from said pole faces to define an air gap between the magnetic member and each of the pole faces, an electroconductive armature mounted for rotation relative to the magnetic structure through the air gaps about an axis between first and second positions, said armature having a portion spaced from the axis positioned for movement through the air gaps, a winding surrounding said first pole piece efiective when energized by an alternating quantity for directing magnetic flux in parallel through said second and third pole pieces, closed winding means surrounding said second pole piece for altering the time phase of magnetic flux passing therethrough to establish a shifting magnetic field within the air gaps, said shifting magnetic field developing a first torque acting between said armature and said magnetic structure to urge the armature toward said second position, said armature having a spiral configuration presenting an increasing efiective portion to said shifting magnetic field as the armature rotates toward said second position whereby the magnitude of said first torque increases as the armature rotates toward said second position in response to constant energization of said winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the armature relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and said armature for biasing the armature toward said first position with a second torque which increases as the armature rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of said armature relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of said armature, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said armature intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, and independent circuit controlling means spaced about said axis responsive to the arrival of said armature at each of said first and second positions, said circuit controlling means being adjustable relative to said armature about said axis to vary the range of rotation of said armature to thereby vary the minimum and maximum values of a variable alternating quantity represented by said first and second positions, said closed winding means comprising an additional winding and an adjustable impedance in series relation with the additional Winding, said impedance being adjustable for varying the impedance offered to current traversing the additional winding produced by voltage induced therein by action of magnetic flux passing through said second pole piece, adjustment of said impedance being etfective to vary the magnitude of said first torque to thereby vary the stationary position of the armature relative to said first and second positions for a constant energization of said winding.

11. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure with first, second and third pole pieces having pole faces disposed substantially in a common plane, a magnetic member spaced from said pole faces to define an air gap between the magnetic member and each of the pole faces, an electroconductive armature mounted for rotation relative to the magnetic structure through the air gaps about an axis between first and second positions, said armature having a portion spaced from the axis positioned for movement through the air gaps, a winding surrounding said first pole piece effective when energized by an alternatlng quantity for directing magnetic flux in parallel through said second and third pole pieces, closed winding means surrounding said second pole piece for altering the t me phase of magnetic flux passing therethrough to establish a shifting magnetic field windin the air gaps, said shifting magnetic field developing a first torque acting between said armature and said magnetic structure to urge the armature toward said second position, said armature having a spiral configuration presenting an increasing effective portion to said shifting magnetic field as the armature rotates toward said second position whereby the magnitude of said first torque increases as the armature rotates toward said second position in response to constant energization of said winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the armature relative to the magnetic structure which has a first slope, biasing means connected between the stator structure and said armature for biasing the armature toward said first position with a second torque which increases as the armature rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of said armature relative to the magnetic structure which has a predetermined second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of said armature, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said armature intermediate said first and said positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, damping means opposing rotation of said armature relative to the magnetic structure with a third torque which varies substantially as a function of the rate of rotation of the armature, and independent circuit controlling means spaced about said axis responsive to the arrival of said armature at each of said first and second positions, said circuit controlling means being adjustable relative to said armature about said axis to vary the range of rotation of said armature to thereby vary the minimum and maximum values of a variable alternating quantity represented by said first and second positions.

12. In a time delay regulating relay device, a magnetic stator structure having an air gap, an electroconductive rotor structure, means mounting the rotor structure for rotation through the air gap about an axis relative to the stator structure between first and second positions, said stator structure including winding means effective when energized for developing a first torque acting between the rotor and stator structures to urge the rotor structure toward said second position, said rotor structure having a configuration presenting a varying elfective portion to the air gap such that said first torque increases in magnitude as the rotor structure rotates toward said second position in response to a constant energization of said winding means, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of said rotor structure relative to the stator structure which has a first slope, biasing means connected between the stator and rotor structures for biasing the rotor structure toward said first position with a second torque which increases as the rotor struc ture rotates toward said second position, said biasing means being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of the rotor structure relative to the stator structure which has a second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of said rotor structure, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said rotor structure intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, said stator structure including adjustable means for adjusting the magnitude of said first torque to thereby adjust the stationary position of said rotor structure relative to said first and second positions for a constant energization of 'said winding means, independent circuit controlling means spaced about said axis responsive to the arrival of the rotor structure at each of said first and second positions, said circuit controlling means being adjustable relative to said rotor structure about said axis for varying the range of rotation of the rotor structure, and magnetic damping means opposing rotation of said rotor structure relative to said stator structure with a third torque which varies substantially as a function of the rate of rotation of said rotor structure.

13. In a time delay regulating relay device responsive to minimum and maximum values of a variable alternating quantity, a stator structure including a magnetic structure with first, second and third pole pieces having pole faces disposed substantially in a common plane, a magnetic member spaced from said pole faces to define an air gap between the magnetic member and each of the pole faces, an electroconductive armature mounted for rotation relative to the magnetic structure through the air gaps about an axis between first and second positions, said armature having a portion spaced from said axis positioned for movement through the air gaps, a first winding surrounding said first pole piece effective when energized by an alternating quantity for directing magetic flux in parallel through said second and third pole pieces, closed winding means surrounding said second pole piece for altering the time phase of magnetic fiux passing therethrough to establish a shifting magnetic field within the air gaps, said shifting magnetic field developing a first torque acting between said armature and said magnetic structure to urge the armature toward said second position, said armature having a spiral configuration presenting an increasing effective portion to said shifting magnetic field as the armature rotates toward said second position whereby the magnitude of said first torque increases as the armature rotates toward said second position in response to constant energization of said first winding, said first torque having a first curve representing the ratio of the magnitude of said first torque to the position of the armature relative to the magnetic structure which has a first slope, a resilient biasing spring member connected between the stator structure and the armature for biasing the armature toward said first position with a second torque which increases as the armature rotates toward said second position, said spring member being proportioned to develop a second torque having a second curve representing the ratio of the magnitude of said second torque to the position of said armature relative to the magnetic structure which has a second slope greater than said first slope to provide a point of intersection of said first and second curves within the range of rotation of said armature, said first and second torques being balanced at said point of intersection to thereby provide a stationary position of said armature intermediate said first and second positions, said first and second positions representing respectively minimum and maximum values of a variable alternating quantity, said closed winding means comprising a second winding and an adjustable impedance in series relation with the second winding, said impedance being adjustable for varying the impedance ofiered to current traversing the second winding produced by voltage induced therein by action of magnetic flux passing through said second pole piece, adjustment of said impedance being eifective to vary the magnitude of said first torque to thereby vary the stationary position of the armature relative to said first and second positions for a constant energization of said first winding, said first winding having a plurality of turns adjustable to vary the magnitude of said first torque independently of the variation effected by adjustment of said impedance, independent circuit controlling means spaced about said axis responsive to the arrival of said armature at each of said first and second positions, said circuit controlling means being adjustable relative to said armature about said axis to vary the range of rotation of said armature to thereby vary the minimum and maximum values of a variable alternating quantity represented by said first and second positions, and magnetic damping means opposing rotation of said armature relative to the magnetic structure with a third torque which varies substantially as a function of the rate of rotation of the armature.

References Cited in the file of this patent UNITED STATES PATENTS 2,485,548 Abbott Oct. 25, 1949 2,504,909 Tubbs Apr. 18, 1950 2,697,187 Sonnemann Dec. 14, 1954 2,752,539 Sonnemann June 26, 1956 2,760,124 Glassbum Aug. 21, 1956 FOREIGN PATENTS 550,795 France Dec. 21, 1922 

